Metadata Collection, Granular Recovery, and Live Browse
To restore files and folders, you must be able to access metadata about files and folders during the browse and restore operation. This can be accomplished in the following ways:
- If the Enable Granular Recovery option is selected when performing the backup of the virtual machine, metadata about files and folders is collected during the backup process. Collecting metadata adds to the time required for the backup. The granular recovery option supports NTFS, ext2, and ext3 file systems, and can be used for Windows file restores or (for streaming backups only) Linux file restores that do not use the File Recovery Enabler for Linux.
Note: The Enable Granular Recovery option is not required for file browse and restore operations. For VMware, this option is disabled by default for new backups or backup schedules created in SP4 or later.
When file and folder metadata is collected during a backup, that information is used for browse and file recovery operations, and you cannot perform a Live Browse.
- If metadata was not collected during a backup, file and folder information can be discovered during a Live Browse operation. Collecting metadata during the browse operation adds to the time required for the browse and restore.
MediaAgents include 3DFS components to enable Live Recovery and Live Mount operations for virtual machines running on Microsoft Windows. You can use the same MediaAgent that was used to perform a backup to restore full virtual machines or guest files and folders, without requiring granular recovery during backups.
The File Recovery Enabler for Linux provides UNIX file system support for ext2, ext3, ext4, XFS, JFS, Btrfs, HFS, and HFS Plus. To enable extended file system recovery for UNIX-based virtual machines, deploy a File Recovery Enabler for Linux or convert a Linux MediaAgent to a File Recovery Enabler.
You can create the CollectVSAGranularMetadata additional setting on CommserveDB.Console to change the default behavior. For example, the following string shows the values that describe the default settings for all hypervisors:
Where ! indicates that metadata is not collected for backups. If a hypervisor is not listed in the string value for this additional setting, the default behavior applies.
- If granular recovery is enabled but some file information could not be read (for example, ext4 data for a Linux VM), partial metadata is collected during the backup, and you can only browse files and folders for which metadata was successfully captured. To enable Live File Recovery to be used in such situations, you can add the bAllowPartialVMMetadata additional setting to the Virtual Server Agent proxy and set the value to false. With that setting, partial metadata for a virtual machine is discarded, enabling Live File Recovery to be used for browse and restore operations. For steps, see Add or Modify an Additional Setting.
To enable Live File Recovery even when the Enable Granular Recovery option is selected, you can configure the nEnforceLivebrowse additional setting on the Virtual Server Agent (VSA) proxy.
- Logical volume manager (LVM) metadata processing for volumes encrypted using BitLocker is currently not supported. Decrypting contents of such volumes may not be feasible during backup because decryption requires a recovery password or a decryption key. Because metadata collection for the volume fails, a file-level browse operation for the encrypted volume cannot display file information.
For more information, see Metadata Collection, Block Level Browse, and Live Browse.